K8s 練習 - part 1

K8s

之前就想玩玩K8s，所以就抽空來玩玩喽~

Install

這邊主要先把minikube裝起來(以下環境為Archlinux)

  1. install virtualbox
    • sudo pacman -S virtualbox
    • 選擇 virtualbox-host-modules-arch
    • sudo modprobe vboxdrv
  2. curl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64 \ && chmod +x minikube
  3. sudo cp minikube /usr/local/bin/. && rm minikube
  4. Install kubectl:
    • curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl
    • chmod +x ./kubectl
    • sudo mv ./kubectl /usr/local/bin/kubectl

start

查看目前版本

$ minikube version
minikube version: v1.0.1

開始，第一次啟動時會跑很久，因為要把環境裝起來

$ minikube start
😄  minikube v1.0.1 on linux (amd64)
💿  Downloading Minikube ISO ...
 142.88 MB / 142.88 MB [============================================] 100.00% 0s
🤹  Downloading Kubernetes v1.14.1 images in the background ...
🔥  Creating virtualbox VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
📶  "minikube" IP address is 192.168.99.100
🐳  Configuring Docker as the container runtime ...
🐳  Version of container runtime is 18.06.3-ce
⌛  Waiting for image downloads to complete ...
✨  Preparing Kubernetes environment ...
💾  Downloading kubelet v1.14.1
💾  Downloading kubeadm v1.14.1
🚜  Pulling images required by Kubernetes v1.14.1 ...
🚀  Launching Kubernetes v1.14.1 using kubeadm ... 
⌛  Waiting for pods: apiserver proxy etcd scheduler controller dns
🔑  Configuring cluster permissions ...
🤔  Verifying component health .....
💗  kubectl is now configured to use "minikube"
💡  For best results, install kubectl: https://kubernetes.io/docs/tasks/tools/install-kubectl/
🏄  Done! Thank you for using minikube!

查看狀態

$ minikube status
host: Running
kubelet: Running
apiserver: Running
kubectl: Correctly Configured: pointing to minikube-vm at 192.168.99.100

$ kubectl cluster-info
Kubernetes master is running at https://192.168.99.100:8443
KubeDNS is running at https://192.168.99.100:8443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy

To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.

config

$ cat .kube/config 
apiVersion: v1
clusters:
- cluster:
    certificate-authority: /home/zonda/.minikube/ca.crt
    server: https://192.168.99.100:8443
  name: minikube
contexts:
- context:
    cluster: minikube
    user: minikube
  name: minikube
current-context: minikube
kind: Config
preferences: {}
users:
- name: minikube
  user:
    client-certificate: /home/zonda/.minikube/client.crt
    client-key: /home/zonda/.minikube/client.key

圖形化操作

$ minikube dashboard

執行hello-minikube:

$ kubectl run hello-minikube --image=k8s.gcr.io/echoserver:1.10 --port=8080
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/hello-minikube created

查看pods狀態:

$ kubectl get pods
NAME                              READY   STATUS              RESTARTS   AGE
hello-minikube-56cdb79778-trxx9   0/1     ContainerCreating   0          108s

對外公開應用:
透過kubectl expose可以讓外面連到hello-minikube這個服務

$ kubectl expose deployment hello-minikube --type=NodePort
service/hello-minikube exposed

$ kubectl get pods
NAME                              READY   STATUS    RESTARTS   AGE
hello-minikube-56cdb79778-trxx9   1/1     Running   0          27m

$ kubectl get services
NAME             TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
hello-minikube   NodePort    10.103.163.153   <none>        8080:30337/TCP   28m
kubernetes       ClusterIP   10.96.0.1        <none>        443/TCP          11h

$ minikube service hello-minikube --url
http://192.168.99.100:30337

連上http://192.168.99.100:30337會出現

Hostname: hello-minikube-56cdb79778-trxx9

Pod Information:
	-no pod information available-

Server values:
	server_version=nginx: 1.13.3 - lua: 10008

Request Information:
	client_address=172.17.0.1
	method=GET
	real path=/
	query=
	request_version=1.1
	request_scheme=http
	request_uri=http://192.168.99.100:8080/

Request Headers:
	accept=text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
	accept-encoding=gzip, deflate
	accept-language=en-US,en;q=0.5
	connection=keep-alive
	host=192.168.99.100:30337
	upgrade-insecure-requests=1
	user-agent=Mozilla/5.0 (X11; Linux x86_64; rv:66.0) Gecko/20100101 Firefox/66.0

Request Body:
	-no body in request-